Effects of Grape Seed Powder as a Functional Ingred ient on Flour Physicochemical Characteristics and Dough Rheological Properties

Abstract

In this study, the effects of incorporating grape s eed powder (GSP) on flour physicochemical properties i.e. particle size, crud e protein, fiber, wet gluten and gluten quality (Zeleny test), and dough rheological proper ties were investigated. Increasing incorporation levels of GSP from 5 to 25% (w/w flou r basis) led to an increase in the amount of fat, total phenol, and total dietary fibe r; whereas total protein, wet gluten, and Zeleny values of the flour blends decreased. The re sults of farinograph test indicated a reduction in water absorption, stability, and farin ograph quality number by increasing the concentration of GSP in the flours. Addition of GSP to wheat flour increased degree of softening and mixing tolerance of dough, while a rrival time was slightly affected. Incorporation level below 10% (w/w) showed no negat ive effect of grape seed on dough rheological performance. There was a good potential in increasing nutritional and health value of bread by incorporating GSP, while keeping attention on the negative effects of the higher concentrations of GSP. Keywords: Farinograph, Omega-3 fatty acids, Rheology, Wheat f lour, Zeleny values.